INDIANAPOLIS — Five schools have reported school-wide flu outbreaks so far this season.

Last season, only one school had reported an outbreak during the same period.

For it to be considered a school-wide flu outbreak, 20% or more of students have to be absent due to illness. Several district representatives tell RTV6 that school nurses can not say for sure when a student is out sick if it's flu-related or another illness. However, to be cautious, some local schools are sending out notices to parents.

Greenfield-Central sent a letter stating that not only is it flu season, but there has been an increase in reports of a stomach virus.

Mount Vernon sent out a letter to parents letting them know there is deep cleaning happening within schools to provide the healthiest environment for students to learn.

Doctors say the strain of flu we see a lot of right now is 'flu b' which usually occurs a bit later in the season.

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